E7F01

What is meant by “direct sampling” in software defined radios?

1. ASoftware is converted from source code to object code during operation of the receiver
2. BI and Q signals are generated by digital processing without the use of RF amplification
3. CIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
4. DA switching mixer is used to generate I and Q signals directly from the RF input

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